Before you can understand the major differences between "have been" and "Has been," you must understand how they are used and what types of pronouns the two go with. For first-person pronouns, we have "I, me, mine," as its singular form, while “we, us, our,” and “ours," are the plurals for the first-person pronouns. All of these pronouns usually go with "have been."
For example, I have been expecting you since last week. Another example: we have been banned from taking part in the examination. For second-person pronouns have been being used mostly to form a present perfect continuous tense.
For example, you have been eating too much lately—however, the major difference between the two lies in their usage with third-person pronouns, for third-person singular pronouns such as “her, his, its, he, her, she, him,” "has been" should be used. However, for third-person plural pronouns such as them, theirs, they, etc. "Have been" should be used.